The present invention relates to a method of producing a waxy maize starch derived from plants and grains which are predominantly heterozygous for the recessive sugary-2 allele by interplanting waxy maize seed which is homozygous for the dominant sugary-2 allele and waxy maize seed which is homozygous for the recessive sugary-2 allele, one hybrid being male sterile. The maize is harvested and processed together to obtain starch with excellent low temperature and freeze-thaw stability, high pasting temperature, and intact granules.
Waxy maize starch which is heterozygous for the sugary-2 allele and its functionality are known in the art and disclosed in U.S. Pat. No. 5,954,883. The typical method of producing such starch is to plant such that the hybrids are alternated one male row then seven female rows. The female rows are then harvested to obtain the waxy maize hybrid which is heterozygous for the recessive sugary-2 allele. The male rows are allowed to go to waste.
This methodology is expensive with the cost of producing the waxy maize which is heterozygous for the recessive sugary-2 allele being at least 10% higher than that for waxy maize.
Surprisingly, it has now been discovered that the two hybrids may be more cost effectively produced by interplanting, harvesting and processing together the resultant hybrids without significantly losing starch functionality.
This patent pertains to a method of producing a waxy maize starch derived from plants and grain which are predominantly heterozygous for sugary-2 allele by interplanting waxy maize seed which is homozygous for the dominant sugary-2 allele and waxy maize which is homozygous for the recessive sugary-2 allele, one hybrid being male sterile. The maize is harvested and processed together to obtain starch with excellent low temperature and freeze-thaw stability, high pasting temperature, and intact granules.
F1 hybrid, as used herein, is intended to mean a hybrid arising from crossbreeding of two inbred lines.
Heterozygous, as used herein, is intended to mean a genetic condition existing when different alleles reside at corresponding loci on homologous chromosomes.
Homozygous, as used herein, is intended to mean a genetic condition existing when identical alleles reside at corresponding loci on homologous chromosomes.
Hybrid, as used herein, is intended to mean any offspring of a cross between two genetically unlike varieties.
Inbred, as used herein, is intended to mean a substantially homozygous variety.
Male sterile or female, as used herein, is intended to mean that the plant does not produce functional pollen as a consequence of any mechanism including without limitation mechanical or hand detasseling (manual), chemical sterility, or genetic sterility such as cytoplasmic male sterility which renders the tassel nonfunctional.
Unless otherwise stated, dominant genes are represented by capital letters and recessive genes by lower case letters. The endosperm of maize is triploid and contains three alleles of a gene. Thus, wxwxwxsu2su2su2 would represent a hybrid which is homozygous recessive for both the waxy gene and the sugary-2 gene while wxxwxwxSu2Su2su2 would represent a hybrid homozygous for the waxy gene and heterozygous for the sugary-2 gene with two dominant or wild alleles and one recessive or mutant allele.